Malaria, one of the world's most important infectious diseases, is transmitted by mosquitoes and is caused by four species of Plasmodium parasites (P. falciparum, P. vivax, P. ovale, P. malariae). Symptoms include fever, chills, headache, muscle aches, tiredness, nausea and vomiting, diarrhea, anemia, and jaundice. Convulsions, coma, severe anemia and kidney failure can also occur. It remains a leading cause of death globally, especially amongst African children under 5 years of age. While repeated infections over many years leads to partial immunity in endemic areas, these adults still suffer significant morbidity and loss of productivity. The annual economic loss in Africa due to malaria is estimated at US $12 billion.
There is no effective vaccine currently available for malaria. Treatment has therefore relied primarily on antimalarial drugs such as chloroquine. Because some malaria parasites have acquired resistance to each available antimalarial drug, there is a desire to discover and develop new antimalarials.